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Abstract:

A sample collection system capable of collecting, storing and dispensing a
liquid sample is disclosed. The collection system includes a collector
composed of a material which has the unique ability to express
constituents of interest at levels which are much more concentrated than
their levels in the fluid samples from which they are expressed, where
the expressed highly concentrated sample can then be used with modern
rapid screening/testing protocols, such as solid phase assays, to test
for the constituents of interest. Thus, it is now possible to obtain
analytes of interest, such as the HIV protein antibodies, from saliva
samples at concentrations that are representative of that found in serum
or plasma. The collector is sized and shaped to fit within a recovery
container, which, in turn, is sized and shaped to fit within a collection
tube. The recovery container includes an aperture which does not permit
passage of fluid under ambient conditions, but facilitates transfer
thereof when subjected to pressure. An optional channel within the
collection tube facilitates dispensing of the sample for further
processing.

Claims:

1. A collector device for use with a saliva sample collection system, said
collector device comprisinga closure for cooperating with a collecting
container, anda collector connected to said closure for insertion into
the collecting container when the closure is connected to the collecting
container, wherein said collector is capable of collecting and storing a
saliva sample including constituents of interest present in the saliva
sample when said collector is strategically positioned in the mouth of an
individual for a sufficient period of time, and wherein said collector is
capable of expressing from the saliva sample constituents of interest in
concentration levels which are representative of the concentrations for
the constituents of interest found in serum or plasma.

2. A collection system for collecting, storing and dispensing a fluid
sample including constituents of interest, said collection system
comprising:a collector;a recovery container; anda collection tube;said
recovery container shaped and sized to seat within said collection tube,
said recovery container occupying less than total volume of said
collection tube;wherein said collector is sized and shaped to removably
fit within said recovery container; andwherein said collector is capable
of collecting and storing said sample; andwherein said collector is
further capable of expressing therefrom constituents of interest in
concentrations levels which are more concentrated than their
concentration levels in the fluid sample from which they are expressed.

3. A method for collecting and storing a fluid sample containing an
analyte of interest and expressing the analyte therefrom, said method
comprising the step of:collecting the fluid sample via use of a collector
capable of concentrating the analyte in a concentration level which is
more concentrated than its concentration level in the fluid sample from
which it is expressed.

Description:

FIELD OF THE INVENTION

[0001]This invention is directed to sample collection devices for
collecting, recovering and storing fluid samples, such as biological
fluids, e.g., saliva, and for expressing constituents of interest
therefrom at levels which are much more concentrated than their levels in
the fluid samples from which they are expressed, and methods of use
thereof.

BACKGROUND

[0002]The analysis and testing of samples for detection of constituents of
interest thereof generally involves initially obtaining a representative
sample and, subsequently, transporting the sample to a laboratory for
constituent analysis. Typically, a sample is collected via some expedient
and transferred to an intermediate device for storage and/or contact with
one or more analytical reagents.

[0003]For example, in the context of the constituent analysis of a
biological fluid sample, the sample is typically collected by invasive
procedures (e.g., finger stick or venous puncture of sample donor for a
blood sample), or is a biological waste (e.g., urine or stool specimen),
depending upon the constituent (analyte) of interest, and the physical
condition of sample donor. The traditional methods for the invasive
collection of biological fluid samples (e.g., drawing blood) is generally
restricted to certain controlled and/or laboratory environments. More
specifically, the securing of a sample, such as by drawing blood,
necessarily involves the consent of the subject, and is often limited in
terms of the size of the sample that can be obtained. Moreover,
traditional invasive procedures generally require trained personnel to
obtain the sample.

[0004]Alternative means of sample collection (e.g., voiding of a urine
specimen) may prove to be an unacceptable option due to the unique
attributes of a vital, biological fluid sample with respect to the
constituents (analytes) of interest. More specifically, certain types of
constituents of interest (e.g., analytes, such as blood borne infections,
cholesterol, triglycerides, blood alcohol, etc.) are not readily
ascertainable from biological waste and, thus, no acceptable alternative
method for analysis exists. Accordingly, the limitation imposed by the
foregoing constraints restricts the clinician/investigator to either a
vital biological fluid (blood or saliva) or, in the case of alcohol, to a
breathalyser type test.

[0005]A vital, biological fluid, such as saliva, is relatively easily
obtained, stable, conveniently stored and contains a number of
constituents of interest to both the clinician and to law enforcement. As
is known, and common in saliva testing, the sample can be readily
obtained by swabbing the buccal epithelial tissues in the donor's mouth,
or through the use of a saliva collection device which is placed in the
donor's mouth for a definitive period of time to allow for the adsorption
of saliva thereon.

[0006]The use of a collection device is preferred in that it protects the
individual collecting the sample from exposure thereto, and otherwise
provides a relatively sterile medium in which to transfer the sample for
storage, or to subject the sample to analysis.

[0007]Traditional methods and devices associated with collection of saliva
samples via collection systems suffer from several major drawbacks.
First, and most important, traditional methods have not heretofore been
capable of providing sufficient concentrations of the analyte of interest
to facilitate modern rapid screening/testing protocols, such as solid
phase assays (e.g., rapid screen HIV testing). Such methods have
produced, even under the most optimum conditions, concentration levels
much below that found in blood, which are generally required for such
modern screening/testing protocols.

[0008]Additionally, the traditional use of cotton swabs and/or plastics as
"absorbents" for saliva collection medium is flawed since such materials
will often introduce residual material (e.g., fibers) into the sample,
thus potentially adversely affecting the sample and limiting, if not
completely precluding, its use. Moreover, the use of a cotton swab is
inherently incompatible with the collection and analysis of proteinaceous
analytes, or protein bound analytes, in that such materials adsorb and/or
otherwise adversely interact with the protein and thereby prevent its
later release for detection and analysis.

[0009]Notwithstanding the foregoing, the use of saliva for constituent
analysis has and continues to be a source of considerable interest and
investigation because of the presence of numerous constituents of
interest (e.g., analytes) in saliva and its accessibility as a test
specimen. Unfortunately, the deficiencies in the techniques and devices
for its collection has up to now postponed its widespread acceptance as a
biological sample of choice.

[0010]Accordingly, there is, and remains, a continuing need to enhance
devices for, and methods associated with, collection of a saliva sample
(e.g., saliva) from a donor which provides sufficient concentration
levels of the constituent of interest and is thereafter subjected to
selective, diagnostic testing with the remainder thereof being stored for
future use and testing (e.g., confirmation testing in the case of drugs
of abuse).

SUMMARY OF THE INVENTION

[0011]In brief, the present invention alleviates and overcomes certain of
the above-mentioned drawbacks, shortcomings and disadvantages of the
present state of the fluid sample collecting art through the discovery of
novel and unique systems for collecting, recovering and storing fluid
samples, such as biological fluids, e.g., saliva, and for expressing
constituents of interest therefrom at levels which are much more
concentrated than their levels in the fluid samples from which they are
expressed, and methods of use thereof.

[0012]Generally speaking, the systems of the present invention are simple,
yet effective and include: (1) a recovery container having an open end
and a closed end, which may include a small aperture; (2) a cap having
means for engagement and sealing of the open end of the recovery
container; and (3) a collector sized and shaped to fit within the
recovery container and, optionally, affixed to the inner surface of the
cap and extending therefrom into the recovery container, when the cap is
engaged with and sealed to the recovery container.

[0013]Alternatively, sample collection systems envisioned by the present
invention for collecting, recovering, testing, storing and dispensing
fluid samples, such as biological fluids (e.g., saliva) include: (1) a
collection tube having an open end and a closed end (optionally tapered),
and optionally including (1a) a sub-assembly, which comprises a recovery
container having an open end and a closed end, including a small
aperture, the recovery container having a size and shape to fit within
the collection tube; (2) a cap having means for engagement and sealing of
the open end of the collection tube; and (3) a collector sized and shaped
to fit within the recovery container and, optionally, affixed to the
inner surface of the cap and extending therefrom into the recovery
container.

[0014]When an alternative system is assembled in accordance with the
present invention, the collector fits within the recovery container,
which, in turn, fits within the collection tube. As the cap is screwed
onto or otherwise removably attached to the collection tube, the cap and
the recovery container exert a force on the relatively larger collector,
expressing some of the sample from the collector into the lower end of
the collection tube via the aperture of the recovery container.

[0015]In accordance with the present invention, the sample collection
systems are preferably used to collect saliva samples. In this context, a
collector is comprised of a poly foam member of sufficient size and void
volume to rapidly collect a saliva sample which is recoverable therefrom
in sufficient quantity and for providing sufficient concentration levels
of constituents of interest to permit analysis and testing thereof,
without elaborate sample preparation or laboratory equipment and
utilizing available methods and techniques. It is believed that, because
the collectors of the present invention absorb moisture from the saliva
samples, but not the analytes under investigation (e.g., hormones,
enzymes, vitamins, proteins, etc.) in the saliva samples, they have the
unique ability to highly concentrate the analytes into concentrations not
heretofore obtainable with traditional sample collection systems
available up to now when expressed therefrom. For example, when an
analyte under investigation in the saliva is a protein, the collectors
have generated, quite surprisingly, testable samples containing protein
in concentrations (in mg/ml) which are at an average percentage increase
of at least about 200% over the concentrations of protein produced from
saliva samples obtained by direct pipette draw. As indicated
hereinbefore, this unexpected result is believed to be due to the ability
of the polymer foam collectors to absorb moisture from the saliva sample
without absorbing the analytes of interest in the saliva sample when the
saliva sample is expressed therefrom.

[0016]As a result, it has been surprisingly discovered that collectors
having this ability, as contemplated by the present invention, can
provide analyte concentrations from saliva that have been unachievable
heretofore. In other words, the present invention now makes it possible
to obtain from saliva, an analyte of interest, such as HIV protein
antibodies, in a concentration which falls within the range that is
representative of that found in serum or plasma. The significance of this
discovery is underscored by the fact that the present invention now
permits analytes to be tested easily, noninvasively and reliably from
saliva, as opposed to having to resort to invasive blood drawing
techniques utilized in the past to obtain testable analyte
concentrations. Thus, it should now be appreciated by those versed in
this art that the collectors of the present invention have the remarkable
ability to concentrate an analyte of interest from saliva to generate a
concentration which is generally obtained from blood, so that the analyte
under investigation can be detected from saliva without having to resort
to blood as the testing sample.

[0017]Also within the contemplation of the present invention, collectors
are treated with a wetting agent that has the ability to modify the
viscous, fibrous and/or gelatinous nature of saliva samples to produce
relatively thin, fluid samples, which are much less viscous and more
readily flowable and, thus, easier to collect and process. Such wetting
agents are generally believed to break down or some how affect the saliva
components, such as mucopolysaccarides, food particles, cells, cellular
fragments, microorganisms and the like present therein, without
interfering with the analytes in the saliva under investigation. Examples
of such wetting agents include any inert surfactant, such as the Tweens,
polyethylene ethyl glycol (PEG), such as PEG 400, and the like.

[0018]Also, in accordance with the present invention, the collectors may
be treated with a salivating agent capable of stimulating the salivation
glands for enhancing salivation by the test subject upon contact of the
subject's mouth therewith. Examples of such salivating agents include
citric acid and flavors, such as lemon, lime, orange and the like.

[0019]In a preferred embodiment of this invention, the recovery container
includes a small aperture in the closed end thereof which permits access
to a fluid within the recovery container: This aperture is essentially
restrictive of fluid transfer under ambient conditions, thus requiring
that a negative or positive pressure be exerted upon the fluid within the
recovery container to effectuate the passage thereof through the aperture
in the collection tube. Likewise the collection tube includes an optional
channel within its closed end capable of providing access to fluid within
the collection tube. Like the aperture of the recovery container, the
channel of the collection tube will not permit fluid passage under
ambient conditions. The application of a force upon the collection tube,
however, will cause fluid to be dispensed from the collection tube for
further processing.

[0020]It is both critical and essential to the efficacy of the present
invention described herein that the collector be matched to the physical
and chemical properties of both the fluid sample and the analytes of
interest contained therein, in that it must be both capable of rapid
absorption and release of the sample and constituent of interest to allow
for analysis thereof without any substantial interaction with or
permanent adsorption of the constituent of interest.

[0021]In a preferred embodiment of this invention, the collector is
comprised of an interconnecting open cell polymer, e.g., polyvinyl
alcohol, foam that is essentially inert (cross-linked) and otherwise
unreactive, e.g., non-adsorbent, toward both the fluid sample and the
analytes of interest within the fluid sample, such as an interconnecting
open cell polymer polyvinyl alcohol foam marketed under the brand name
Clinicel. Moreover, the poly foam material of the collector should be
first treated with a salivating agent and a wetting agent, in accordance
with the present invention, so as to stimulate the salivation glands to
enhance salivation and to modify the fluid sample from its natural
viscous, fibrous and/or gelatinous state to a relatively thin and fluid
sample, respectively. Accordingly, it has been surprisingly found that
the collectors of the present invention provide significantly higher
concentrations of constituents of interest, e.g., analytes, from fluid
samples than has been achieved using known collection systems available
heretofore.

[0022]The poly foam material of the collectors, and other comparable or
suitable materials, can be formulated or selected, as desired, to have
the requisite density, porosity and other physical properties consistent
with the inherent characteristics of the absorbed fluid and the
contemplated method of sample recovery and analysis.

[0023]In another preferred embodiment of this invention, the physical
shape of the absorbent foam element roughly parallels the shape of the
interior of the sample recovery member and is slightly larger (length
and/or width) in size. Although the collector has a comparatively small
profile (generally 50 to 60% of volume of the collection tube), the
slightly larger size of the collector provides an important function of
the system; namely, the expression of a portion of the sample as a result
of fastening the cap to the tubular collection member. As the cap is
brought into intimate contact with and fastened to the open end of the
collection tube, the force exerted by the cap and the recovery container
on the slightly larger collector to cause it to fit within the recovery
container, causes the fluid sample to be expressed into the substantially
closed end of the collection tube, providing the sample for further
analysis.

[0024]In yet another of embodiment of this invention, either the cap
and/or the closed end of the collection tube (including the optional
aperture) can be further modified to provide a fitting, e.g.,
sub-assembly, for coupling or physically engaging (mating with) a fixture
which includes an analyte sensitive element, e.g., test kit. Thus, upon
coupling of the collection system and the fixture, it is thereupon
possible to direct or focus the dispensing of the fluid contents of the
collection system onto the analyte sensitive element within the fixture
to facilitate analysis thereof. More specifically, each of the cap and/or
the substantially closed ends of the collection tubes of the collection
system, and a fixture for an analyte sensitive element, can each be
modified to engage the other so as to create leak proof union of the two
and thereby provide a fluid pathway from the collection tube to a fluid
receiving component of the fixture for the analyte sensitive element.
Thus, subsequent to, or concurrent with, recovery of the fluid sample
from the fluid absorbent element (e.g., squeezing the foam via fastening
of the cap) in the collection tube of the collection system, it can be
directly applied from the reservoir within the collection tube onto the
test element without any loss or inadvertent contact with the clinician.
Moreover, since only the requisite amount of sample to perform the assay
is used, the balance is conserved for re-testing or simply retained
within the secure environment of the collection system, thus insuring
against its cross-contamination and/or infection of unsuspecting
individuals.

[0025]The volume of saliva that is collected by the fluid absorbent
element is a function of: the size of the absorbent element; the
composition of the absorbent element, and, of course, the time the
element is in contact with the donor. A typical saliva collector of this
invention has a fluid absorbent element of sufficient size and fluid
capacity to absorb and thereafter release (express) a sufficient volume
of saliva (from approximately 100 to 200 microliters) for performance of
at least one screening assay and at least one conformation assay (if
required). As more fully set forth herein, the volume of sample
contemplated for use in the solid phase immunoassays of interest will
generally require at least approximately 50, and preferably,
approximately 100 microliters.

[0026]An important feature of the present invention is the ability of the
sample collection system to provide the relatively large concentration
levels of sample constituents of interest required for modern rapid
testing/screening procedures, such as solid phase assays.

[0027]The above features and advantages of the present invention will be
better understood with reference to the following Figs., Detailed
Description and Examples. It should also be understood that the
particular embodiments and methods illustrating the present invention are
exemplary only, and are not to be regarded as limitations of the present
invention.

BRIEF DESCRIPTION OF THE FIGURES

[0028]With reference to the accompanying Figs., which are illustrative of
certain embodiments scope of the present invention:

[0029]FIG. 1 is a perspective view of a preferred embodiment of a sample
collection system of this invention;

[0030]FIG. 2 is an exploded view of the sample collection system of FIG.
1, which includes a sample recovery or collection tube and cap of
composite construction;

[0031]FIG. 3 is an enlarged view of the closed end of the collection tube
of FIG. 2, wherein the closed end of the collection tube includes an
orifice which defines a fluid pathway through the end of the collection
tube;

[0032]FIG. 4 is a perspective view of an embodiment of the sample
collection system wherein the collection tube component includes a skirt;

[0033]FIG. 5 is a perspective view of an embodiment of the sample
collection system in cooperative relationship with a test icon;

[0034]FIG. 6 is an exploded perspective view of a preferred embodiment of
the sample collection system;

[0035]FIG. 7 is a perspective view of an embodiment of the sample
collection system as an element of a "test kit";

[0036]FIG. 8 is perspective view of the test kit of FIG. 7 in a
workstation embodiment;

[0037]FIG. 9 is a table outlining the results of a study designed to
determine the protein concentration capabilities of the unique collectors
of the present invention;

[0038]FIG. 10 is a table outlining the results of a study designed to
determine the protein concentration and absorbed weight and retrievable
volume of unique collectors of the present invention;

[0039]FIG. 11 is an exploded perspective view of another preferred
embodiment of the sample collection system;

[0040]FIG. 12 is a table outlining the percentage yield of protein for the
unique collectors of the present invention;

[0041]FIG. 13 is a table outlining the protein analysis for the unique
collectors of the present invention;

[0042]FIG. 14 is a table outlining the results of a study following a
Bio-Rad protein assay protocol designed to determine the protein
retention capabilities of the unique collectors of the present invention;

[0043]FIG. 15. is a table illustrating a standard Bio-Rad absorbance curve
for three different BSA standard solutions with known concentrations,
i.e., 3 mg/ml, 2 mg/ml and 1 mg/ml;

[0044]FIG. 16 is a table outlining the results of a study following a
Bio-Rad protein assay protocol designed to determine the protein
retention capabilities of the unique collectors of the present invention
when expressing three different BSA standard solutions with known
concentrations, i.e., 3 mg/ml, 2 mg/ml and 1 mg/ml, and water; and

[0045]FIG. 17 is a table outlining the results of a study designed to
determine the protein concentration capabilities of alternative
collectors of the present invention.

[0046]It will be understood that the particular Figs. embodying the
present invention are shown by way of illustration only and not as
limitations of the present invention. The principles and features of the
present invention may, therefore, be employed in various and numerous
embodiments without departing from the scope or spirit of the present
invention.

DETAILED DESCRIPTION OF THE INVENTION

[0047]By way of illustrating and providing a more complete appreciation of
the present invention and many of the attendant advantages thereof the
following detailed description and examples are provided concerning the
novel sample collector systems, embodiments, alternatives and methods.

[0048]For ease of understanding and continuity of expression, a numerical
reference has been assigned to each component part of the system of this
invention based upon the function of the component in the system. Thus, a
component of a specific combination having the same function in the
combination is present in a system of more than one of the Figs., the
last two numbers of the assigned reference numeral will be the same in
each of the Fig. where such common function is illustrated. For example,
in applying this convention to the functional component of the sample
collection system designated as a "cap" (which is functionally designated
with the numerical reference "114" in FIG. 1), the caps of the collection
system in subsequent Figs. are thus labeled with related reference
numerals ending in "14" (e.g., "214" for FIG. 2, "314" for FIG. 3, and so
on).

[0049]As is discussed more fully herein, the design and operation of the
various components of the sample collection system all cooperate to
collect a fluid sample (e.g., saliva) including one or more constituents
of interest in sufficient volume and at a higher concentration than
normally representative of the environment from which it has been
obtained, and thereafter permit recovery of an aliquot of such fluid
sample for constituent analysis. Importantly, such aliquot of fluid
sample is provided by the collection system of the present invention,
including sufficient concentration levels of constituent(s) of interest
which are representative of that found in serum or plasma, so as to
permit its use with modern rapid screening/testing protocols, such as
solid phase assays.

[0050]The present invention incorporates these multiple functions into a
single, yet simple system. Now referring to FIG. 1, the basic structure
of the system 110 is illustrated. The system 110 is comprised of four (4)
primary components: (1) a collection tube 112; (2) a cap 114 for,
alternatively, sealing and accessing the collection tube 112; (3) a
recovery container 116 shaped and sized to seat within the collection
tube 112; and (4) a collector 118 for collection (adsorption) of a liquid
sample, (e.g., a biological fluids sample, such as saliva).

[0051]The recovery container 116 has one or more apertures 120 associated
with its lower portion to permit passage of the sample from the recovery
container 116 to the collection tube 112. The collection tube 112 has an
optional channel 122 associated with it so as to provide an alternative
method of obtaining an aliquot of the sample from the collection tube
112. Each of the four primary elements will be discussed below.

A.) Collection Tube

[0052]Now referring to FIG. 2, in each of the embodiments of this
invention, the collection or centrifuge tube 212 has an open end 212o and
a closed end 212c. The open end 212o of the collection tube 212 is of
sufficient diameter to accommodate the insertion and removal of a
recovery container 216 (discussed below), and is further provided with
either external threads 209, or an equivalent, e.g., snaps, inter-locking
teeth, tapered fit or the like, for sealing engagement by a screw lid or
complementary snap, inter-locking or tapered cap 214 (discussed below),
such as shown in FIG. 11.

[0053]Referring now to FIGS. 1, 2 and 11, the collection tube 112 or 212
or 1112 of the collection systems 110, 210 or 1110, respectively, of this
invention can have a tapered bottom configuration, depending upon its
intended uses, a flexible (and resilient) sidewall construction and
versatility for configuration with other functional components of the
system. In another of the alternative embodiments of this invention, the
collection tube 112, 212 or 1112 can be prepared from a relatively rigid
material, e.g., thermoset plastic or glass. In alternative embodiments,
an optional fixture (shown in FIGS. 4 and 5) is associated with the
collection tube 112 to assist with dispensing an aliquot of the sample
for further processing.

[0054]An optional feature of the embodiments of the sample collection
system of the present invention is the presence of a channel 122 within
the closed end 112c of the collection tube 112. As further illustrated in
FIG. 3, the channel 322 is preferably centrally located within the closed
end 312c of the collection tube 312. The channel 322 is preferably shaped
and sized such that the sample will not leak from the collection tube 312
under ambient conditions. However, if the collection tube 312 is
subjected to pressure, e.g., during centrifuging, an aliquot of the
sample may be obtain via the channel 322. Optionally, a screen (not
shown) or other selective pass-through device may be used in connection
with channel 322 to filter the sample as it is being removed from the
collection tube 312. Although a channel appearing within the surface of
the closed end 312c of the collection tube 312 is described herein, it is
noted that the present invention contemplates the use of other means for
accessing/preventing access to the sample via the collection tube 312,
including, by way of illustration and not limitation, the use of a
tapered dispensing tip (with optional quantitative marks for measuring
sample volume), a pressure-activated valve, pierceable septa, e.g.,
vacuum collection tubes, or other suitable devices.

B.) Cap

[0055]As illustrated in FIG. 2, an exploded view of the sample collection
system of FIG. 1, the cap 214 is of composite construction and is,
optionally, removably (or permanently) attached to the collector 218 of
the sample collection system 210. In FIG. 6, there is shown an embodiment
of the collection system 610 having the collector 618 separate from the
cap 614. In FIG. 11, a cap or stopper 1114 is depicted which is separate
from the collector 1118.

[0056]Referring now again to FIG. 2, in this embodiment of the collection
system 210, the open end 212e of the collection tube 212 is provided with
a threading 209 complementary to threading (not shown) along the interior
of the cap 214. When mated (via screwing the collection tube 212 within
the cap 214), the open end 212o of the collection tube 212 and the cap
214 form an air tight seal to prevent leakage and/or contamination of a
collected sample.

[0057]Referring now to FIG. 11, in this embodiment of the collection
system 1110, the open end 1112o of the collection or centrifuge tube 1112
is tapered internally which is complementary to the tapering (not shown)
along the exterior of collar 1119 of recovery tube 1116. When mated via
tapering, i.e., the exterior of the collar 1119 of recovery tube 1116 and
the tapered interior of collection tube 1112, the open end 1112o of the
collection tube 1112 and the recovery tube 1116 form an air tight seal to
prevent leakage and/or contamination of a collected sample expressed into
the collection tube 1112.

[0058]Alternate embodiments of the invention optionally include holes,
vents or channels (424 & 524 in FIGS. 4 and 5, respectively) in the cap
214 to permit vapor and/or gas (e.g., air) that is trapped within the
sample recovery tube 212 to be expelled at the time of releasing the
sample from the sample absorbent medium into the collection tube 212.

C.) Recovery Container

[0059]As illustrated in FIG. 2, the recovery container 216 is sized and
shaped to fit and seat within the collection tube 212 and receive the
collector 218. Preferably, but not mandatory, having a flexible sidewall
construction for finger squeezing, the recovery container receives the
slightly larger collector 218 and, as more fully described below, plays a
role in providing expression (release) of specimen from the collector 218
to collection tube 212. It should appreciated by those of skill in this
art that any materials suitable for permitting the sidewall construction
of the recovery container, designated for example as 116, 216, 616 and
1116, to be finger squeezed can be utilized for purposes of expressing
the fluid sample from the collector and assisting the flow of the fluid
sample.

[0060]The one or more apertures 220 of the recovery container 216 are
preferably shaped and sized such that the sample will not leak from the
recovery container 216 under ambient conditions. However, if the recovery
container 216 is subjected to negative pressure, e.g., during
centrifuging, an aliquot of the sample may be obtain via the channel 220.
Although an aperture appearing within the surface of the closed end of
the recovery container 216 is described herein, it is noted that the
present invention contemplates the use of other means for
accessing/preventing access to the sample within the recovery container
216, including, by way of illustration and not limitation, the use of a
tapered dispensing tip (with optional quantitative marks for measuring
sample volume), a pressure-activated valve, pierceable septa, e.g.,
vacuum collection tubes, or other suitable devices.

[0061]The slightly smaller length and circumference of the recovery
container 217 as compared with the collector 218 provides the pressure
required, upon placement and attachment of the cap 214, to release a
portion of the sample held within the collector 218 into the lower
portion of the collection tube 212.

[0062]It should of course be understood that when the recovery container
216 is designed with a flexible side wall construction, it may be finger
squeezed to express the fluid sample, e.g., saliva, absorbed onto the
collector 116.

[0063]As illustrated in FIG. 11, the recovery container 1116 is sized and
shaped to fit and seat within the collection tube 1112 and receive the
collector 1118. Preferably, but not mandatory, having a flexible sidewall
construction for finger squeezing, the recovery container 1116 receives
the slightly larger collector 1118 and, as more fully described below,
plays a role in providing expression (release) of specimen from the
collector 1118 into collection tube 1112.

[0064]The aperture 1120 of the recovery container 1116 is preferably
shaped and sized, e.g., 0.075'', such that the sample will not leak from
the recovery container 1116 under ambient conditions. However, if the
recovery container 1116 is subjected to negative pressure, e.g., during
centrifuging, an aliquot of the sample may be obtain via the channel
1120. Although an aperture appearing within the surface of the closed end
of the recovery container 1116 is described herein, it is again noted
that the present invention contemplates the use of other means for
accessing/preventing access to the sample within the recovery container
1116, including, by way of illustration and not limitation, the use of a
tapered dispensing tip (with optional quantitative marks for measuring
sample volume), a pressure-activated valve, pierceable septa, e.g.,
vacuum collection tubes, or other suitable devices.

[0065]The slightly smaller length and circumference of the recovery
container 1117 as compared with the collector 1118 provides the pressure
required, upon placement and attachment of the cap 1114, to release a
portion of the sample held within the collector 1118 into the lower
portion of the collection tube 1112.

[0066]It should again be understood that when the recovery container 1116
is designed with a flexible side wall construction, it may be finger
squeezed to express the fluid sample, e.g., saliva, absorbed onto the
collector 1116.

D.) Collector

[0067]Referring again to FIGS. 1 and 11, as previously noted the sample
collection system 110 or 1110 of this invention is capable of use in a
variety of environments and thus its specific construction is dictated
accordingly. More specifically, where the collection system 110 or 1110
is to be used to collect a fluid sample containing a hazardous waste
comprising a highly acidic substance of organic substance, the materials
selection for the components of the collection system 110 or 1110 must be
resistant to degradation by the sample. Similarly, where the collection
system 110 or 1110 is to be used in the collection of a biological fluid,
such as saliva, the materials selection for the collection tube and the
collector 116 or 1116 must exhibit at a minimum the following
characteristics: (1) inert with respect to proteins, vitamins, enzymes,
hormones and other like constituents of interest (collectively
"analytes") of the sample; (2) not subject to ingestion or chemical
breakdown from intimate contact with enzymes or other components
contained in the saliva; (3) not capable of leaching any substances into
the mouth of the donor during collection or thereafter; (4) capable of
rapidly collecting and subsequently releasing a biological fluid to allow
for the analysis of the constituents contained therein; (5) capable of
modifying the sample collected from its viscous, fibrous and/or
gelatinous nature into a relatively thin fluid sample; and (6) capable of
providing a sufficient concentration level of sample constituents of
interest so as to facilitate employment with modern rapid
screening/testing protocols, such as solid phase assays.

[0068]In the preferred embodiments of this invention, the collector 118 or
1118 for a saliva collection system 110 or 1110 of this invention is an
inert material which exhibits a three dimensional, open and
interconnecting cell structure (e.g., foam) having characteristics
consistent with the foregoing sample collection and analysis
requirements. In the preferred embodiments of this invention, the
collector 118 or 1118 is formed of a water insoluble material, e.g.,
catalyzed polyvinyl alcohol polymer, of the type available from M-PACT,
Intech Business Park, 1040 OCL Parkway, P.O. Box 618, Eudora, Kans. 66025
under the CLINICEL trademark. Alternative materials that are believed to
be suitable for the collectors of the present invention include, for
example, expanded, cellular (sponge/foam) silicone materials marketed by
Ipotec, Inc., 41 Industrial Drive, Exeter, N.H. 03833, hydrophilic
polyurethane sponge materials, such as Hydrasorb®, available from
Avitar Technologies, Inc. 65 Dan Road, Canton, Mass. 02021, and
styrene-butadiene, such as white FDA sponge materials approved by the
FDA.

[0069]These CLINICEL® brand polyvinyl alcohol sponges are soft and
pliable when wet and semi-rigid when dry. The highly absorbent sponges
are lint- and fiber-free and are capable of rapidly absorbing up to
twenty (20) times their dry weight in fluids. Additionally, hydrocarbons,
acids, alkalines and most chemicals do not adversely affect this sponge
material. The Clinicel® polyvinyl alcohol sponges are believed to be
stable toward enzymes and serological fluids, behave in water as a
negatively charged colloid and strongly absorb metallic cations, such as
copper or iron. The Clinicel® polyvinyl alcohol sponges are also
believed to have a strong affinity for cationically charged ions of the
quaternary ammonium type.

[0070]Importantly, such Clinicel® polyvinyl alcohol foam sponge
material is capable of providing sufficient concentration levels of
sample constituents of interest that are representative of that found in
plasma or serum to facilitate use of the sponge material with modern
rapid screening/testing protocols, such as solid phase assays, e.g.,
rapid HIV tests. As more specifically described below and in FIGS. 9, 10,
12 and 13, testing of such sponges demonstrates that they are capable of
providing concentration levels of constituents of interest from saliva
samples of at least about 5.0 mg/ml., and, more preferably, of at least
about 7.5 mg/ml. By comparison, this 7.5 mg/ml concentration is at an
average percentage increase of at least about 200% over direct pipette
draw of saliva samples.

[0071]The processing conditions and composition of the foam sponge are
geared to provide a very high adsorption density and sufficient tensile
strength to withstand the rigors of sample collection and thereafter the
recovery thereof by the compression of the foam so as to express the
sample into the collection tube via the recovery container where it can
be contacted with an analyte sensitive element or dispensed onto a test
strip analysis.

[0072]Preferred foams for use with the collection system of the present
invention are capable of being molded to size and/or compressed, such as
the Clinicel® polyvinyl alcohol sponge materials. In the context of
this invention, the collector can be formed by simple and well-known
fabrication methods, such as traditional molding or die cutting to shape.
The sponges can also be trimmed by hand via scissors or like cutting
devices.

[0073]It should be appreciated that anhydrous water-miscible solvents,
such as ethyl alcohol or propylene glycol, or solutions of hygroscopic
salts, such as calcium chloride, will dehydrate moist Clinicel®
polyvinyl alcohol sponge materials and render them temporarily hard,
which may be useful to facilitate the cutting and shaping of them. After
fabrication of the desired shapes of the Clinicel® polyvinyl alcohol
sponges, the hardening agent(s) can be thoroughly removed therefrom by
washing in water.

[0074]The collector 118 or 1118, as illustrated in FIG. 1 or 11,
respectively, is shaped to approximate the internal upper space within
the recovery container 116 or 1118, e.g., about 0.50'' OD×1.7'' in
length. The collector 118 or 1118 is sized to be slightly larger (in
length and circumference) such that a force is required to completely
contain the collector 118 or 1118 within the recovery container 116 or
1116. This force can be provided when the cap 114 or 1114 is placed over
and attached to the collection tube 112 or 1112, providing release of a
portion of the sample from collector 118 or 1118 into the lower portion
of the collection tube 112 or 1112 via the aperture 120 or 1120 of the
recovery container 116 or 1116, respectively.

[0075]Referring now to FIG. 6 or 11, the collector 618 or 1118 may be
separate from the cap 614 or 1114 or attached (removably or permanently)
via traditional methods (FIG. 2), including in-place molding of the
collector to the cap or providing complementary threading on the upper
end of the element and inside the cap, so that the collector may be
screwed into and out of close contact with the cap. Although molding and
complementary threading is described herein, it is noted that any other
suitable method for attaching or otherwise associating the collector 618
or 1118 to the cap 614 or 1114 may be used in connection with the sample
collection system of the present invention. For example, the collector
618 or 1118 may be affixed to the cap 614 or 1114 via a light curing
adhesive, such as ECCOBOND® UV 9110, which is recommended for medical
plastic bonding application and is available from W.R. Grace & Co.-Conn.

[0076]As alternate embodiment of the present invention, the collectors may
be treated with a salivation enhancing agent, such as citric acid or
flavors for stimulating a person's saliva production. Examples of
appropriate flavors for stimulating the salivation glands include lemon,
lime, orange or the like. Additionally, the collectors of the present
invention may be pretreated with wetting agents, such as the TWEENS®,
propylene ethyl glycol (PEG) such as PEG 400, etc., to modify the fluid
sample from its natural viscous, fibrous and/or gelatinous state to a
relatively thin and fluid sample. Generally speaking, this may be
accomplished by simply creating a solution of these agents and soaking
the collectors therein for a sufficient period of time as, described
hereinafter in the Examples.

[0077]In addition, after the collectors are pretreated in accordance with
the present invention, they may be lyophilized using standard
lyophilizing techniques known in the industry for storing the collectors
until use.

E.) Other Embodiments

[0078]As illustrated in FIG. 4, the sample collection system 410 may
include a collection tube 412 associated with another collection/testing
device, such as a skirt 420. The skirt 420 is preferably provided with
complimentary threading along its upper portion so that the skirt 420 can
be removably attached to the cap 414. Although complimentary threading
attachment is described herein, it is noted that any suitable means for
removably associating the skirt 420 with the collection tube 412 may be
used. The skirt 425 provides the function of collecting sample from the
collection tube 412 for further analysis/processing without subjecting
the sample to ambient conditions, i.e., avoiding contamination of the
sample, and/or without exposing the surrounding environment to the
collected sample, i.e., avoiding contamination/infection by the sample.

[0079]An alternate embodiment of the design of the collection tube 412 is
also illustrated in FIG. 4. In this embodiment, the closed end of
collection tube 412 is generally rounded.

[0080]Now referring again to FIGS. 1 and 11, as previously discussed, the
collection tube 112 or 1112 of the collection device 110 or 1110 is
preferably of a flexible or rigid sidewall construction, and preferably
transparent to allow for observation of the sample within the sample
recovery tube 112 or 1112. Thus, once the sample has been collected on
the collector 118 or 1118 and the collector 118 or 1118 inserted in the
recovery container 116 or 1116, the collection tube 112 or 1112 is sealed
with the cap 114 or the collar 1119 of recovery tube 1116, respectively.

[0081]It is desirable from both a consumer and manufacturing perspective
to provide one or more basic designs for the sample collection system of
the present invention and yet permit the adaptation thereof to a
particular application or user preference without departure from such
basic design concept(s).

F.) Sample Collection and Recovery

[0082]In the preferred method of use of the system of this invention, the
sample is obtained by contact (or immersion) of a collector with a source
of a fluid suspected of containing an analyte of interest. Although the
collection of a biological fluid is primarily described herein, it is
noted that the system and method for use thereof of the present invention
applies equally to the collection of other types of samples. For example,
in the context of analysis of waste water for a toxic substance (e.g.,
heavy metals, organic, etc.), a representative sample of the waste water
is obtained and the collector simply immersed within the sample.
Regardless of the type of sample collected, the amount of such sample
that need be absorbed to perform the desired analysis is determined
ultimately by the analytical protocol, and it is assumed preferred
swabbing/immersion procedures will supply more than adequate sample for
the intended analysis.

[0083]Referring again to FIG. 1, employing the method of the present
invention to collect a sample in the context of constituent analysis of
saliva, the collector 118 of the system 110 can be readily adapted to the
age of the donor (infants, toddlers, adults) and otherwise have varying
porosity to make it more or less absorbent. Alternatively, the system 110
can be used with the other traditional biological fluids, (e.g., urine,
whole blood, serum, etc.) and its design may thus vary accordingly. In
each instance, the sample is obtained by first removal of the collector
118 from within the recovery container 116, the sample collected as above
described and the sample collector 118 placed within the recovery
container 116. If separated from the collection tube 112, the recovery
container 116 is next placed within the collection tube 112 prior to be
sealed therein using the cap 114. The act of securing the cap 114 will
release at least a portion of the sample into the lower portion of the
collection tube 112. In alternate embodiments and assuming that an
adequate (by volume) sample has been obtained, it can thereafter be
released by any one of a number of techniques, depending upon the
configuration of the system 110 of the present invention, and once
recovered, subject to constituent analysis. For example, in the preferred
embodiments, the sides of the recovery container 116 are squeezed so as
to compress the collector 118 therein and thereby release the sample from
the collector 118 into the lower end of the collection tube 112 via the
aperture 120 of the recovery container 116. Once the sample is released,
the physical separation of the sample within the collection tube 112 from
the collector 118 in the recovery container 116 prevents the recontact of
the collector 118 with the released portion of the sample in the closed
end of the collection tube 112.

[0084]Referring now to FIG. 11, employing a method of the present
invention to collect a saliva sample in the context of constituent
analysis of saliva, the foil pack (not shown) in which the 1110
collection system is packaged, is opened and the cap 1114 is pulled from
the foil package and placed between the cheek and gum of a subject for
about two minutes or until the foam collector 1118 has expanded and is
thoroughly wetted by the saliva. After removing the collector 1118 from
the subject's mouth, and holding the collector 1118 only by the cap 1114,
the collector 1118 is reassembled into the recovery tube 1116 by twisting
gently to insert the wet collector 1118. The recovery tube 1116 is seated
within the collector or centrifuge tube 1112. To sample or test, the
recovery tube 1116 is pulled from the collector tube 1112 by the cap
1114, and while holding the cap 1114, the flexible recovery tube 1116 is
finger squeezed to express into the collection tube 1112. If necessary,
centrifugation can improve the yield. At this point, one or more selected
test strips, such as the One Step strip tests from TCPI, may be inserted
into the collection tube 1112 for direct analysis of the now highly
concentrated saliva sample. Alternatively, the highly concentrated saliva
sample may be transferred using a calibrated dropper pipette contained
in, for example, TCPI's cassette type devices, e.g., TCPI's RAPIDTEST
HIV® devices.

[0085]Again, depending upon the specific configuration of the device of
this invention, the collection and recovery of a representative sample of
fluid is accomplished with relative ease and security. Although not
generally recommended when dealing with samples containing a toxic and/or
infectious agent, the cap 114 simply can be removed from the system to
permit access to the sample within the collection tube 112, and an
analyte sensitive element and/or chemicals added into the collection tube
112 and allowed to interact with the recovered sample. This method of
analysis is generally undesirable since it needlessly exposes the
clinician and the environment to the used collector 118 and the contents
of the collection tube 112.

[0086]Where the sample is, however, suspected of containing infectious
organisms, the preferred embodiment of the system selected will insure
that once the sample has been obtained, it is retained within the secure
environment of the recovery container 116 and thereafter only supplied
for analysis in a manner that prevents contamination of the ambient
environment and those persons that must have access thereto for purposes
of analysis.

[0087]Where the device of this invention does not afford access to the
sample via a dispensing orifice integral with the device, or other means,
the sample is generally obtained by first releasing the sample from the
collector 118 through the one or more openings 120 within the recovery
container 116 into the reservoir at the closed end 112c of the collection
tube 112, and then removing the cap 114 and recovery container 116 from
the open end 112o of the collection tube 112 of the collection system 110
(which also results in the collector 118 being withdrawn from the
collection tube 112). An aliquot of fluid sample can thereafter be
withdrawn from the collection tube 112 with a pipette, or the sample
simply transferred to another vessel for analysis, by pouring the sample
from the tube into the test vessel or via the optional channel 122
located in the closed end 112c of the collection tube 112 and described
above. After at least some of the sample has been removed from the
collection tube 112, the collector 118 and recovery container 116 are
replaced within the collection tube 112 and the collection tube 112 is
sealed with the cap 114 for storage or disposal.

[0088]The flexible sidewall design of the recovery container 116 permits
the recovery of the sample from the collector 118 by compressing the foam
within the tube, where the samples passes through the one or more
apertures 120 in the recovery container 116 and collects in the reservoir
in the bottom (closed end 112c) of the collection tube 112. The provision
of an optional vent/channel (424 & 524 in FIGS. 4 and 5, respectively) in
the cap 114 can improve the sample recovery process without compromising
the sealing of the system by providing a way for pressure within the
tubes to equalize as the sample is being released from the collector 118
and dispensed from the collection tube 112, thus minimizing the
potentiality for damage to collection system 110 during the sample
recovery process.

[0089]As is apparent from the above, the collection and recovery of the
sample within the system of the present invention is only the beginning
of the process for the determination of the presence of the analyte of
interest, and, in some instances, the amount thereof. In order to
accomplish such analysis, an aliquot of sample is contacted with an
analyte sensitive element that is specific for the manifestation of the
presence of the analyte of interest. In its simplest form, the analyte
sensitive element can be one or more chemicals that are reactive with the
analyte of interest, or alternatively, an elaborate chemistry system. In
each instance, the analyte sensitive element can be contacted directly
with the sample by the placement thereof into the recovery container
and/or the collection tube, or an aliquot of sample withdrawn/dispensed
from the sample recovery tube and reacted with the analyte sensitive
element in a test environment that is independent of the collection
device of this invention.

[0090]In the simplest embodiment of this invention, an aliquot of sample
can be removed from the collection tube through the use of a pipette,
straw or like device. As noted above, the preferred sample handling
routine involves the use an embodiment of the collection system including
the aperture and/or a vent or channel to facilitate dispensing of a
recovered sample without removal of the cap and the collector from the
sample recovery tube.

[0091]As illustrated in FIG. 5, an embodiment of the collection system 510
is shown including an associated collection accessory (skirt 520). In
this Figure, the collection system 510 is shown in use with an external
test station 560. Using such an arrangement, an aliquot of sample is
passed from the collector 518 into the reservoir located at the closed
end 512c of the collection tube 512 via the aperture 520 of the recovery
container 516 by the methods previously described (e.g., manual squeezing
or centrifuging). Once the sample is located in the closed end 512c of
the collection tube 512, the closed end 512c of the collection tube 512
is brought into close association with the test station 560 and an
aliquot of the sample is passed from the collection tube 512 to the
testing station 560. Prong 526 of the testing station 560 is used to
access the sample within the collection tube 512 via channel 520.
Reagents associated with the analysis to be performed by the test station
560 are located in association with the test disk 575. Following contact
of the sample with the reagents of the test disk 575, the test is read to
determine the results thereof,

[0092]Now referring to FIGS. 7 and 8, there is shown an embodiment of the
sample collection system 710, 810 as a component of a "test kit" 777,
877. Such test kits typically include all of the accessories (e.g., unit
packages of reagents) and reagent system(s) needed to complete the
desired analysis. For example, the sample collection system 710 is
uniquely suited for use with a rapid screening for human immunodeficiency
virus (HIV), the causative agent of Acquired Immune Deficiency Syndrome
(AIDS), such as the RAPIDTEST HIV® SCREEN available from Technical
Chemicals & Products, Inc., P.O. Box 8726, Ft. Lauderdale, Fla. 33310
(TCPI).

[0093]While serum has been the sample of choice for such tests, saliva
samples can now be successfully employed. Using the RAPIDTEST HIV®
SCREEN protocol for saliva samples, the sample collection system 710 of
the present invention is used for sample collection. The cap is removed
and the collector is withdrawn from within the recovery container. Next,
the collector is placed between the cheek and gum of the test subject for
approximately 4 minutes or until the collector has expanded and is
thoroughly wetted. Once the collector is removed from the mouth of the
test subject, it is re-inserted into the flexible recovery container by
twisting generally. See FIG. 11. The next step of the protocol includes
releasing the sample from the collector via manual or finger squeezing or
centrifuging, if required, to concentrate and drive the sample to the
bottom of the collection tube. See FIG. 11. The sample is now ready to be
combined with reagents, allowed to react and read for results.

[0094]FIG. 8 illustrates the sample collection system of the present
invention used in connection with a workstation-type test kit.

[0095]As previously discussed, one of the most important aspects of the
sample collection system of the present invention is the use of a
collector which is capable of collecting, storing and providing a sample
having concentration levels of sample constituents of interest which are
representative of that found in serum or plasma, so as to facilitate
modern rapid screening/testing protocols, such as solid phase assays.
Prior to this discovery by the inventors of the present invention, simple
and inexpensive sample collections systems were incapable of delivering
such a highly concentrated sample from, for example, saliva.

[0096]Various embodiments and results of the present invention will now be
further illustrated with reference to the following examples. For
instance, the following examples illustrate the dramatic increases in
concentration levels of sample constituents of interest obtainable using
the sample collection system and, more specifically, the unique collector
of the present invention.

EXAMPLE I

[0097]Referring now to FIGS. 9, 12 and 13, there is shown testing and data
resulting therefrom associated with sample concentration levels produced
using traditional sample collection methods (direct draw via pipette) as
compared with the sample collection system of the present invention. As
demonstrated in the Table of FIG. 9, the average percentage increase of
protein concentration obtained by the present invention over the amount
obtain using traditional direct draw methods is 220%. Accordingly, the
present invention provides a clear advantage over prior art direct draw
techniques associated with fluid sample collection.

[0098]A sample collection system of the present invention using
Clinicel® polyvinyl alcohol sponges is treated with a citric acid
buffer-ovalbumin wash before being lyophilized. The purpose is to
determine (1) the percentage protein yield of the Clinicel® polyvinyl
alcohol sponges that are treated with a citric acid buffer-ovalbumin
wash, (2) if the addition of the ovalbumin significantly increases the
protein content, and (3) will the saliva sampler, constructed with
Clinicel® polyvinyl alcohol sponges that are treated with a citric
acid-PEG buffer, produce a higher protein concentration than saliva drawn
directly from the mouth via a plastic pipette. Five subjects volunteered.

[0100]Two bags containing 250 each of Clinicel® polyvinyl alcohol,
sponges are rinsed twice with about 375 ml of the filtered citric acid
buffer solution, 2 M. The solution is ringed out of the Clinicel®
polyvinyl alcohol sponges while they are still in their bags.
Approximately 250 ml of the filtered citric acid buffer--ovalbumin
solution, 2M is added to each of the two bags of Clinicel® polyvinyl
alcohol sponges and the sponges are squeezed for about 5 minutes.
Thereafter, the sponges are incubated for about one hour. The sponges are
again rinsed twice with about 375 ml of the filtered citric acid buffer
solution, 2 M, and squeezed as dry as possible within the bags. The
treated Clinicel® polyvinyl alcohol sponges are then laid out flat and
straight on a flat pan and are freeze dried on small virtis. The treated
Clinicel® polyvinyl alcohol sponges are frozen for about one hour, and
are then condensed under vacuum. The pretreated Clinicel® polyvinyl
alcohol sponges are then glued to the caps of the collector system with a
light curing acrylate adhesive, e.g., ECCOBOND® UV 9110.

[0101]The average percentage yield is about 25% or about 580 microliters.
See FIG. 12. This is more than adequate to run a strip test, such as the
RAPIDTEST HIV® SCREEN, which requires at least about 100 microliters.

[0102]To determine if the addition of about 0.02% ovalbumin increases the
protein concentration, one pretreated Clinicel® polyvinyl alcohol
sponge is soaked in deionized water and is tested in unison against the
blank and saliva samples. The water soaked sample shows 0 mg/ml protein
(same as the blank). Therefore, the addition of 0.02% ovalbumin is
negligible. See FIG. 9.

[0103]The protein concentrations for each subject on the saliva sampler is
notably higher than those obtained via direct draw. See FIG. 9. The
average percentage increase of protein (in mg/ml) of samplers over direct
draw is about 220%, as is shown in FIG. 9. In FIGS. 9, 12 and 13, the
white collection device is the Clinicel® polyvinyl alcohol sponge and
the blue collection device is Avitar's Hydrasorb® sponge.

EXAMPLE II

[0104]As demonstrated in the Table of FIG. 10, the sample collection
system of the present invention using a Clinicel® polyvinyl alcohol
sponge produced higher sample constituent of interest (protein)
concentrations than those produced using Avitar's Hydrasorb® sponges.
In this test, collectors constructed with either a Clinicel® polyvinyl
alcohol sponge or an Avitar's Hydrasorb® sponge are used to collect
saliva samples. Saliva samples are collected by placing the sponge being
tested in the mouth of the test subject. The sponges are left in place
for a period of about ten (10) minutes. Next, the sponges are weighed to
record the weight of the saliva absorbed. Then the sponges are
centrifuged for one (1) hour to release the sample from the collector.
Thereafter, the volume of saliva released is recorded. Finally, the
protein content of the collected saliva is determined according to
Bio-Rad analytical method. The average results for four (4) test sponges
of each type are set forth in the Table of FIG. 10. As illustrated, while
the average weight (1.45 grams vs. 1.27 grams) and protein concentration
(7.4 mg/ml vs. 4.9 mg/ml) are significantly increased using Clinicel®
polyvinyl alcohol sponges as the collector versus Avitar's Hydrasorb®
sponge as a collector, respectively, the average retrieval volume (250
μl vs. 500 μl) actually decreased. This result only highlights the
capability of the Clinicel® polyvinyl alcohol sponges as the collector
of the present invention to increase the concentration of the
constituents of interest from a saliva fluid sample. The capability to
produce such significant increases in concentration levels allows the
saliva sample collection system of the present invention to be utilized
with modern rapid screening/testing protocols, such as solid phase
assays.

EXAMPLE III

[0105]The purpose of this experiment is to determine if the Clinicel®
polyvinyl alcohol sponges and treatment protocol affect protein retention
capability.

[0106]12,200 Clinicel® polyvinyl alcohol sponges are ordered and
treated as follows with 91.5 L of citric buffer--PEG 400 wash. Using an
appropriate size clean tank and mixer, approximately 91.5 L of processed
water, about 4575 g sodium citrate, about 577.4 g citric acid, about 4.6
g PEG 400 and about 18.3 g methylparaben are mixed together until
dissolved at about 5.52 pH. One third of solution is separated into
another clean tank for combining with about 6.1 g of ovalbumin. Remove
the required quantity of sponges from the freezer and allow to thaw. This
may be done up to 24 hours in advance. Discard any discolored sponges.
Squeeze each bag of sponges to remove residual liquid. Filter ovalbumin
solution through appropriate 0.2 micron filtration device. Deliver about
0.5 L of filtered ovalbumin solution to each bag of sponges, squeeze and
allow to soak for one hour. Squeeze each bag to remove liquid after
soaking. Filter the initial solution through appropriate 0.2 micron
filtration device. Deliver about 0.5 L of filtered solution to each bag
of sponges, squeeze to rinse again to dry. Repeat this rinse using
another about 0.5 L of filtered solution per bag of sponges. Sponges
should be semi-dry after rinsing and squeezing. Loosely arrange sponges
in each bag to prevent excessive clumping or bending. Sponges may be
frozen prior to lyophilization. Lyophilize allowing the bags to remain
open. When lyophilization is completed, remove the sponges from the
dryer, seal each bag, place into foil pouch, label with lot number and
quantity and store at room temperature.

[0107]Five pretreated Clinicel® polyvinyl alcohol sponges are soaked in
either water, about 3 mg/ml BSA standard solution, about 2mg/ml BSA
standard solution or about 1 mg/ml standard solution for about 5 minutes.
Each sponge is then squeezed and the liquid expressed from the sponges is
collected in appropriately labeled collection tubes. Dilute all BSA
sponge solutions and standards so absorbances will fit the standard
curve. Follow Bio-Rad protein assay procedure in which absorbances can be
read at 750 nm. Results are shown in FIG. 14. In addition, according to
FIG. 15, the average absorbance for 3 mg/ml BSA solution is about 0.25,
for 2 mg/ml solution is about 0.18 and for 1 mg/ml is about 0.9. Further
results are shown in FIG. 16, wherein (1) the five sponges exposed to the
3 mg/ml BSA solution, samples 1-5 therein in FIG. 16, expressed protein
in a concentration on average of about 3.04 mg/ml, (2) the five sponges
exposed to the 2 mg/ml BSA solution, samples 6-10 therein in FIG. 16,
expressed protein in a concentration on average of about 2.16 mg/ml, (3)
the five sponges exposed to the 1 mg/ml BSA solution, samples 11-15
therein in FIG. 16, expressed protein in a concentration on average of
about 1.11 mg/ml, and (4) the five sponges exposed to water, samples
16-20 therein in FIG. 16, expressed protein in a concentration on average
of about 0.018 mg/ml.

EXAMPLE IV

[0108]Three different Avitar Hydrasorb® sponges, designated as blue,
green and plain, are evaluated as collectors in accordance with the
present invention. The evaluation method involves three individuals. The
amount of time that the Avitar sponges are in the mouths of the
individuals varies from about 10 minutes (2 subjects) to about 30 minutes
(subject). The performance of the Avitar Hydrasorb® sponges are
determined by: (1) weight of saliva absorbed, (2) volume of saliva
retrievable after centrifugation for one hour, and (3) the protein
content of the collected saliva which is determined by an analytical
method available from Bio-Rad. The results indicate no significant
difference in the weight of saliva absorbed or the volume of saliva that
is collected between the blue or green Avitar Hydrasorb® sponges. See
FIG. 17. However, the plain Avitar Hydrasorb® sponge is about 28%
lower in both categories. The protein content varies about 508% amongst
the sponges with the blue Avitar Hydrasorb® sponge having the highest
value at about 5 mg/ml. See FIG. 17.

[0109]The present invention may, of course, be carried out in other
specific ways that those herein set forth without departing from the
spirit and essential characteristics of the present invention. Thus, even
though certain embodiments of sample collection systems envisioned by the
present invention have been illustrated in the accompanying Figures and
described in the foregoing Summary of the Invention, Detailed Description
and Abstract, it will be understood that the invention is not limited to
the embodiments disclosed, but contemplates numerous rearrangements,
modifications and substitutions without departing from the spirit of the
present invention, as set forth and defined by the following claims. For
example, the present invention contemplates those various alternative
sample collection systems disclosed and described in PCT International
Application No. PCT/US96/16075 and PCT International Publication No. WO
97/12681, which are incorporated herein by reference in their entireties,
so long as the objectives of the present invention are followed and not
defeated. The present embodiments are, therefore, to be considered in all
respects as illustrative and not restrictive and any changes coming
within the meaning and equivalency range of the appended claims are to be
embraced therein.